Posted By Gilah Kahn Hoffman On October 3, 2010 @ 12:00 am In | No Comments

Two scientists, one from Israel and one from Nablus in the Palestinian Authority are working together to improve water purification for the region and beyond.

Photo by Dani Machlis.

Aiming for more clean water – Dr. Moshe Herzberg from Ben Gurion University.

Clean water is one of the most vital resources in water-scarce countries like Israel and the Middle East, so it’s no surprise that two scientists – one Israeli and one Palestinian – are now working together to increase the supply throughout the region.

Their project addresses the problems of biofouling of Reverse Osmosis (RO) membranes during reclamation of secondary wastewater. Herzberg explains: “Biofouling is what happens to any surface submerged in water. Take a bath toy that’s been in the water for a few days,” he tells ISRAEL21c, explaining that the slimy layer that forms on the surface is the “water-solid interface” that forms where water meets the surface of an object. Microbial communities of bacteria and fungi grow in that interface, also referred to as a matrix, or biofilm.

Now instead of a bath toy, imagine a piece of equipment that filters organic materials and compounds out of sewage or wastewater. On one side, the treated water is perfectly clean, but on the other, active side that is in contact with the smelly stuff, a biofilm forms and builds up over time, adversely affecting performance and necessitating cleaning and replacement of equipment. The cleaning cycles that the filters undergo to remove the biofilm reduce their lifespan and the equipment is very expensive to replace.

Less energy, more clean water

Oh – ‘Reverse Osmosis’ – that’s “the most easily applicable technology for removal of salts and small organic compounds from water,” rendering it safe for irrigation and drinking, adds Herzberg.

The researchers plan to characterize and eventually find novel ways to eradicate different biofilms grown on RO membranes. “If we are able to understand how the biofilm forms and how to reduce its formation on reverse osmosis technology [equipment], we will be able to operate reverse osmosis units for a longer time,” says Herzberg.

Herzberg is confident that he and Ali-Shtayeh will achieve that understanding, since the research, he says, is “based on solid hypotheses that will enable us to come up with optimized operating and cleaning conditions for reverse osmosis plants.”

The reverse osmosis units will require less maintenance and be able to operate for longer periods. Also, the higher performance will render the whole process more cost-effective. “You will need less energy – membrane buildup and cleanup, equipment, labor – to get more clean water,” Herzberg declares.

“These techniques can be applied to increase access to clean water supply in the Middle East, especially in the Palestinian Authority and Israel. Purified secondary wastewater is an immediate resource for irrigation and after RO filtration those waters can be used indirectly for drinking,” he adds.

They will also have wider application: “Other applications include any water and wastewater treatment processes that include filtration units such as ultra-micro- and nano-filtration. Also, ways for biofouling control in other systems such as heat-exchangers and water distribution systems could be improved,” he tells ISRAEL21c.

Applying research to enhance quality of life

The MERC Program funds collaborative research projects between Israel and its Arab neighbors and has funded activities with participation from Egypt, Jordan, Morocco, the West Bank/Gaza and others. Its goal is to contribute to the development and improvement of the quality of life in the Middle East through the application of research and technology; while at the same time contributing to the peace process by establishing cooperative relationships like this one.

While the five-year collaboration is in its early stages, Herzberg says that “so far it seems to be working well. We already have a PhD student from Nablus who will hopefully do his research at BGU.”

In Israel, Herzberg believes that the results of the research should have an almost immediate effect on increasing the country’s supply of clean water. Change will take longer in the Palestinian Authority and the Gaza Strip, however, he warns. “First, tertiary wastewater must be made available from plants that will be constructed, and there are many political and bureaucratic factors to consider,” he explains.

Herzberg predicts that Mekorot [Israel's national water company]will be able to use our data within months for better operation of its pilot plants, like the Shafdan Center in Rishon Lezion, the biggest wastewater treatment plant in Israel that treats all the sewage of the Tel Aviv municipality. They have pilot-plants for desalination of wastewater and they have biofilm problems that our findings will enable them to reduce.”

In addition to Herzberg and Ali-Shtayeh, the other researchers on the project are Dr. Osnat Gillor (BGU) and Dr. Helen Thanh Nguyen, a grant advisor and assistant professor at the University of Illinois Urbana-Champaign. Herzberg and Gillor are both at the Zuckerberg Institute for Water Research which is part of BGU’s Jacob Blaustein Institutes for Desert Research.